1. Field of the Invention
The present invention generally relates to a chair with a tiltable seat and more particularly, to a chair with a tiltable seat and a tiltable backrest mounted on a backrest support.
2. Discussion of Background
Chairs with tiltable seats and tiltable backrests are known, for example, from any of the publications, as follow: EP-A 0834271; EP-B 0489961; and EP-B 0233974. The chairs known from these publications have tiltable seats and tiltable backrests, wherein the seat and the backrest are forceably connected to each other via a so-called xe2x80x9csynchronized mechanism.xe2x80x9d These chairs have a great track record in practice. However, they are not optimal in that the user is dependent upon the connection of the angles of inclination of seat and backrest as specified by the synchronized mechanism. The user is not able to adjust the backrest tilt to a certain position, and to change the inclination of the seat in such a position.
The present invention is meant to resolve the above-stated problem with conventional chairs having tiltable seats and tiltable backrests.
An object of the present invention is to provide a chair having a tiltable seat and a tiltable backrest such that the inclination of the tiltable seat can be adjusted individually, independent from the inclination specified by a synchronized mechanism which depends upon the tilt of the tiltable backrest. Such a chair is important not only for office areas, where the user must be able to adjust the chair under ergonomic aspects to his respective working position, but also in private applications, where the user wants to be able to adjust the respective seat and backrest inclination for relaxation purposes. Further, the present invention provides a chair that is simple in design, is easy to manufacture in the production process, and has a visually aesthetically satisfactory effect.
The object of the present invention is accomplished by providing a chair with tiltable seat and a tiltable backrest both of which are mounted on a backrest support of the backrest of the chair. The chair includes a pedestal mounted on a bottom of the tiltable seat. The pedestal includes an eccentric disk seated in an articulating or movable manner. The eccentric disk is penetrated eccentrically by a rod connected with the eccentric disk in a stationary manner (i.e., the rod is hexagonal and penetrates a hexagonal aperture in the disk so that the rod is not movable with respect to the disk). The rod includes a handle for turning the rod, wherein the handle is mounted on an outer end of the rod. An arm is provided so as to extend upwardly from the backrest support and the rod is seated in the arm in an articulating or movable manner. The rod has a prismatic cross-section (i.e., hexagonal) and penetrates the eccentric disk in a first prismatic cross-section recess (i.e., hexagonal). The handle has a second prismatic cross-section recess (i.e., hexagonal) and with this second prismatic cross-section recess, the handle can be pushed onto an end of the prismatic cross-section rod in a stationary manner (i.e., the is no movement at the connection between the handle and the rod). The prismatic cross-section of the rod and first and second prismatic cross-sectional recesses are hexagonal in shape. The eccentric disk has an outer shell surface which has a lug thereon. In an end position of the eccentric disk, the lug rests against a stop in the pedestal. The stop in the pedestal is offset by more than 180xc2x0 in relation to the lowest bearing point of the lug.
When the seat is supported by the backrest support of the backrest, the distance between the seat and the backrest support can be changed manually by a simple eccentric bearing. While it is true that the seat basically follows the inclination of the backrest, the seat can still additionally be adjusted individually with regard to its inclination in a fixed position of the backrest.